All shotgun sports require the shooter to accurately predict the trajectory of the target. Mastering the lead is the greatest challenge in shotgunning sports. The lead is defined as the distance in front of the moving target, which the shooter aims and shoots at in order to break the target. The particular lead will vary, depending on the application, shot type, shot speed, shooter's technique, speed and angle of the target, and atmospheric conditions; it can range from a few inches to more than ten feet.
The visibility of an object to the human eye generally depends on the size of the object, the relative distance between the object and the observer, the relative speed of the object, the color of the object, and the light intensity and atmospheric conditions. The human brain and eye refresh images approximately every 0.1 seconds, while the average shot flight time to the target ranges from approximately 0.05 to 0.3 seconds; this makes shooting moving objects a real challenge.
Inventors have developed tracers for shotgun shells in an attempt to aid the shooter in visualizing his or her shot with regard to the target. Prior inventions can be categorized as non-ignition and ignition type tracers. Each type has its limitations, including the risk of fire with pyrotechnic tracers and the complexity of manufacturing in the case of chemiluminescent tracers. Both types share a significant drawback: the fact that the shooter has a mere fraction of the second to see the tracer. This makes current inventions of limited value to shooters in providing a consistent and visible reference to aid them in correcting their shooting.
The prior art includes the following inventions:    1. Shot-Shell (U.S. Pat. No. 1,304,962 to J. Gravely in 1919);    2. Shotgun Shell (U.S. Pat. No. 1,457,337 to E. Barrows in 1923);    3. Method and Apparatus for Forming Letters and Symbols in the Air (U.S. Pat. No. 1,716,794 to J. Remey, 1929);    4. Shotgun Cartridge (U.S. Pat. No. 1,887,990 to H. Brownsdon in 1932);    5. Artificial Production of Fog (U.S. Pat. No. 1,895,765 to U. Muller in 1933);    6. Method for Creating Aerial Effects (U.S. Pat. No. 2,062,511 to J. Haddock in 1936);    7. Tracer Shotshell (U.S. Pat. No. 3,262,390 to R. Cowles in 1966);    8. Apparatus for Producing Smoke or Fog (U.S. Pat. No. 3,244,641 to D. Durr in 1966);    9. Method and Means for Producing and Controlling the Discharge of Fog (U.S. Pat. No. 3,379,373 to R. Roberts in 1968);    10. Nebulizer (U.S. Pat. No. 3,652,015 to G. Beall in 1972);    11. Shotgun Shell Tracer Wad (U.S. Pat. No. 4,553,481 to V. Ricci in 1984);    12. Method and Apparatus for Sky Typing (U.S. Pat. No. 4,561,201 to G. Sanborn in 1985);    13. Efficient Artificial Smoke Generator (U.S. Pat. No. 4,836,452 to J. Fox in 1989);    14. Aerosol Diffusion Fogger (U.S. Pat. No. 5,057,243 to M. Becker in 1991);    15. Diffusion Fogger (U.S. Pat. No. 4,990,290 to J. Gill in 1991);    16. Tracer Cartridges (U.S. Pat. No. 5,429,054 to R. Topping in 1995);    17. Smoke Generator for Radio Controlled Aircraft (U.S. Pat. No. 5,932,978, to J. Geyer in 1999);    18. Compression Cartridge (U.S. Pat. No. 6,250,228 to F. King in 2003);    19. Shotgun Shell Flight Path Indicator (U.S. Pat. No. 6,539,873 to E. W. Diller in 2003);    20. Ballistic Tracer Platform for Shotgun Ammunition (U.S. Pat. No. 10,656,471 to J. Dunnam and M. Quintana in 2007).
An improved design would overcome the drawbacks of the prior art and would fulfill the following criteria:                (a) Provide the shooter with a consistent and accurate reference to the target.        (b) Give the shooter more time to see the tracer with reference to the target; in other words the improved design should have memory.        (c) Be safe to use and environmentally friendly.        (d) Be simple and economical to manufacture.        (e) Be entertaining to the shooter.        